中点算法画填充圆实验报告

中点算法画填充圆实验报告实验题目中点算法画填充圆。中点画圆算法内容：1，输入圆心位置和圆的半径，得到圆周上的第一个点Point1;（假设起始点为坐标原点，后面将通过坐标平移来处理非圆心在圆点）2，计算决策关键参数的初始值，P=5/4-r;3，在每个Xn的位置，从n=0开始,更具决策值P来判断：如果P<0,下一个点的位置为(Xn+1,Yn);并且执行P=P+2*x+3;如果P>=0,下一个点的位置为(Xn+1,Yn-1);并且执行P=P+2.0*(x-y)+5;4，通过对称原理计算其他7个对称相关点；5，移动坐标到圆心点(x1,y1)X=X+x1;Y=Y+y1;6，如果X<Y重复执行3到5的步骤，否则结束该算法源代码：#include<GL/glut.h>GLintxc=0;GLintyc=0;intp[200][200];classscreenPt{ private: GLintx,y; public: screenPt(){ x=y=0; } voidsetCoords(GLintxCoordValue,GLintyCoordValue){ x=xCoordValue; y=yCoordValue; } GLintgetx()const{ returnx; } GLintgety()const{ returny; } voidincrementx(){ x++; } voiddecrementy(){ y--; }};voidsetPixel(GLintxCoord,GLintyCoord){ p[xCoord][yCoord]=1;//设置边缘色为1 glBegin(GL_POINTS); glVertex2i(xCoord,yCoord); glEnd();}voidcirclePlotPoints(GLintxc,GLintyc,screenPtcircPt){ setPixel(xc+circPt.getx(),yc+circPt.gety()); setPixel(xc-circPt.getx(),yc+circPt.gety()); setPixel(xc+circPt.getx(),yc-circPt.gety()); setPixel(xc-circPt.getx(),yc-circPt.gety()); setPixel(xc+circPt.gety(),yc+circPt.getx()); setPixel(xc-circPt.gety(),yc+circPt.getx()); setPixel(xc+circPt.gety(),yc-circPt.getx()); setPixel(xc-circPt.gety(),yc-circPt.getx());}voidcircleMidpoint(GLintradius){ screenPtcircPt; GLintp=1-radius; circPt.setCoords(0,radius); voidcirclePlotPoints(GLint,GLint,screenPt); circlePlotPoints(xc,yc,circPt); while(circPt.getx()<circPt.gety()){ circPt.incrementx(); if(p<0) p+=2*circPt.getx()+1; else{ circPt.decrementy(); p+=2*(circPt.getx()-circPt.gety())+1; } circlePlotPoints(xc,yc,circPt); }}voidgetPixel(intx,inty,int&Color){ Color=p[x][y];}voidsetPixel2(GLintxCoord,GLintyCoord){ //p[i][j]=1;填充色为2 p[xCoord][yCoord]=2; glColor3f(0.0,1.0,1.0); glPointSize(5); glBegin(GL_POINTS); glVertex2f(xCoord,yCoord); glEnd();}voidboundaryFill4(intx,inty,intfillColor,intborderColor){ intinteriorColor; getPixel(x,y,interiorColor); if((interiorColor!=borderColor)&&(interiorColor!=fillColor)){ setPixel2(x,y); boundaryFill4(x+1,y,fillColor,borderColor); boundaryFill4(x-1,y,fillColor,borderColor); boundaryFill4(x,y+1,fillColor,borderColor); boundaryFill4(x,y-1,fillColor,borderColor); }}voidrenderScene(void){ glClear(GL_COLOR_BUFFER_BIT); gluOrtho2D(-500,500,-500,500);glPointSize(3); circleMidpoint(30); boundaryFill4(100,100,2,1); glFlush();}intmain(intargc,char*argv[]){glutInit(&argc,argv);glutInitDisplayMode(GLUT_RGB|GLUT_SINGLE);glutInitWindowPosition(100,100);glutInitWindowSize(400,400);glutCreateWindow("一个OpenGL程序");glutDisplayFunc(&renderScene);glutMainLoop();return0;}运行结果：实验总结：这次试验总的来说，就是